Mutation of p53 gene is the most frequently found genetic disorder in human cancers including oral cancer. Though the exact role of p53 gene mutation in carcinogenesis remains unknown, recent studies have suggested that the p53 mutation induces genomic instability and may make cells more susceptible to DNA damage induced by genotoxic agents. Interestingly, several recent studies have demonstrated the presence of anti-p53 antibodies in the sera of some cancer patients bearing tumors with p53 gene point mutations. The correlation between the presence of anti-p53 antibodies and clinical prognosis of cancer remains unknown, but such correlation has never been made in oral cancer. In this project, we therefore plan to investigate whether there is correlation between the autoimmune response of p53 protein and the clinical status of human oral cancer. This pilot project is expected to provide preliminary information regarding the correlation of the presence of anti-p53 antibodies and prognosis of oral cancer. This study may lead to large scale studies to determine the clinical value of the anti-p53 antibodies in foreseeing the prognosis and in determining the treatment protocols for oral cancer.